Clip clinching tool



Aug- 4, 1953 w. D. CHILTON I 2,647,814

CLIP CLINCHING TOOL Filed Feb. '7, 1949 2 Sheets-Sheet l nventor Aug. 4, 1953 w. D. CHILTON CLIP CLINCHING TOOL Filed Feb. 7, 1949 2 Sheets-Sheet 2 ff ff f f /f 'ai 2 y www( Patented ug. 4, l1.953

2,647,814 CLIP CLINCHING TooL William-D. Chilton, Royal Oak, Mich., assigner to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application February 7, 1949, Serial No. 74,956

7 Claims.

This invention relates to apparatus for applying a band or clip about the girth of a .Wire or other elongated work piece, or bundle of such work pieces, and is particularly adapted for binding together adjacent wiresfor example adjacent sections of wire seat springs.

The primary object of the invention is to provide a relatively light weight, power operated, hand portable tool in which the steps of feeding a pre-formed U-shaped clip, grasping the wires or other elements to be bound, and clinching the clip thereabout are carried out automatically in a single continuous rapid operation requiring lthe use of only one hand of the operator.

Another object of the invention is to provide a power operated clip clinching tool wherein, during each clip clinching operation, part of the power is employed to provide a continuously directed force to move the clip into the clinching die and the remainder of the power is employed to effect an intermittent or hammering force on the` clip, the magnitude of the latter force increasing progressively as the movement of the clip decreases in reaching its final clinched position.

Still another object of the invention is to provide a clip clinching tool having a clip magazine attached thereto and adapted to serve as a tool supporting hanger, the magazine being so constructed as to permit substantially unrestrained maneuvering of the tool during use without interfering with the feed of clips thereinto.

` Still another object of the invention is to provide -a tool for clinching pre-formed U-shaped clips of the type having alternately toothed arms, including a clip receiving throat, means for yieldably retaining a clip therein ready for use, and means insuringproper alignment of the clip during its passage from the throatto a clinching anvil.

Other objects relate to the structural organization and arrangement of parts hereinafter described and claimed.

In the accompanying drawings:

Figure 1 is a top plan view of the tool embodying my invention, with portions broken away and in section, and showing the parts in clip clinching position.

Figure 2 is an enlarged sectional view of the cylinder end of the tool taken substantially on line 2-2 of Figure 1, except that the air control valve and associated elements `at that end of the tool are shown rotated 56 from their true position.

Figure 3 is an enlarged 'View of the jaw end` 0I the tool similar to that of Figure 1 except .with the parts in position to begin a clip clinching operation.

Figure 4 is an enlarged sectional view taken substantially on line 4-4 of Figure 5.

Figure 5 is a fragmentary side View of the jaw end of the tool, with portions broken away and in section and showing the parts in clip clinching relation as in Figure 1.

Figure 6 is a detail sectional view of the feed magazine taken substantially on line 6 6 of Figure 5.

Figure 7 is an enlarged perspective View of an unclinched U-shaped sheet metal clip of wellknown form and representative of the type which the tool of my invention is designed to clinch around one or a bundle of wires or the like.

The embodiment of the tool shown in the drawings comprises a frame I including a cylinder 2 closed at one end 3 and connected at its opposite end to a bifurcated or yoke-shaped head 4. The base 5 of the yoke-shaped head has an aperture 6 in line with the bore 'I of the cylinder 2 and supports spaced arms or plates 8 and 9 terminating in nose portions I0 and I I having pockets or notches I2 and I3, respectively, for receiving work of elongated section such as wires I4 and I5.

Pivotally swingable between the plates 8 and 3 about pivots such as bolts I6 and Il are a pair of oppositely disposed jaws in the form of rockers I8 and I9 which extend generally longitudinally with respect to the cylinder 2. The hook-shaped outer ends 20 and 2I of the rockers overlap when brought together, their inwardly curved faces 22 and 23 cooperating with each other in that position to form a female die or anvil, such that when a pre-formed U-shaped clip 24 (Figure 7) is forced legs foremost thereinto its legs 25 and 26 are bent around the wires I4, I5 in the manner illustrated at 25 and 26 in Figure 5. The inner ends of the rockers I8 and I9 carry rollers 21 and 28 and are biased toward each other by springs 29 and 30 `which are tensioned between pins 3I, 32 and 33,34 secured to the rockers and the plate 9, respectively. Slots 35 and 36 are provided in vthe plate 9 to allow clearance for movement of the pins 33 and 34 accompanying swinging of the doors dii and All denne the forward extremities of the clip loading station and serve to` properly position the clip 2li therein preliminary to forcing the same toward the outer ends 28 and 2l of the rockers. A small permanent maghet d'9 projects through the plate 9 between the wall members 3l and 33 and serves to temporarilyretain the clip 24 and insure its being fully seated against the plate 9 in the loading station prior to beginning its passage forwardly to the anvil.

Thespiral springs is and 45 allow the doors 40 and ll to open by swinging forwardly when force is applied to the clip 24 to move it toward the anvil; and in their open position these doors form a continuation of the wall members 3l and 3g for guiding the clip in its passage. The opposite ly disposed faces 5t and 5 1 rearwardly adjacent the inwardlyurved anvil forming faces 2 2 and 23 on the rockers I8 and le cooperate with eachother in the anvil forming position to guide the clip 24 during its passage after it leaves the doors 40 and 4l.

The means for forcing the clip 2li against the anvil consists of a projectable pusher member 52 terminating in a clip engaging nose portion et at its forward end. The inember 52 is slidably guidedbytheplates 8 and nSlinone plane and by the `wall irlernbersI and 3 8 in the plane at right angles thereto. Rearwardly yof its nose portion G3, meniber 621s provided with cam surfaces vSli and 6 5 projecting from its opposite sides for engaging and spreading apart the rollers 2l and 28` duingjorward movement of the member $32, whereby the hook-shaped outer ends and 2l of the rockers are forced together to form an anvil and receive the clip as itis forced thereinto. Qonnected to the rear end of the pusher member 62 is a piston indicated generally by the numeral 66, responsive to f iuidpressure rearwardlythereof in the cylinder 2. The pistont constitutes a fluid pressure operated p'ercnssive hammer, the elements and function of which per s e constitute no partof the instant invention, Included in this hammer device is a cylinderl within which is reciprocated a plunger 6B which strikes the the rear side of the plate valve 7l. Fluid within the cylinder (il and rearwardly of the plunger 68 rear en d of the clip pusher member 62. The

automatic valvemechanism 69; through which the pressureuid is alternately admitted to oppo- 'site ends of the hammer cylinder 6l' to effect the reciprocaticn of the plunger 68, is secured to the rearend ofcylineler 6] by a longitudinally apertured cap which pilots thehammer device in thebore] of the enclosing cylinder 2. A flexible packing 5 1 carried by the cap 'Hl provides a pres'- sure s eal between the cap and the cylinder bore l.

12 indicates means such as a coil spring for bias- 'ing the percussivehammer (piston SS) toward the rear end S of the cylinder 2.

As shown in Figure 2 the valve means includes a thin plate valve 'll which is shiftable to permit pressure fluid to how across either one is in communication with the right side of the plate valve H by means of a passage 'i8 formed in the valve body, and both sides of the plate Valve l'I are at all times subjected to iluid pressure within the bore I rearwardly of the piston 66 b`y way of a passage 19` formed in this valve body. In the position of the parts as shown in 'Figure 2 the plunger 68 has just completed its forward or power stroke, and the plate valve 'Il shifted to its forward position, which shuts o'if the flow of pressure fiuid from the passage l5 to' the left-hand e'nd of the cylinder 5i via the passage 13, and permits such pressure uid to flow ac ross the rear face of the plate valve and ytl'iroug'h the passage Tl and port 'I3 to the rightharid end of the cylinder 6l. As the pressure builds up in this end of the cylinder, the plunger $8 is driven to the left, during which movement it covers the port lt thereby trapping uid in the left-hand end of the cylinder and building up pressure against the front face of the plate valve ll. Shortly thereafter the plunger 68 uncovers the port ill wl'iich drops the pressure in the righthandend of the cylinder, Since this end of the cylinder is connected to therear side of the plate v alveby means of the port 'i3 and passage 'l1 this drop in pressure reduces theforce holding the plate valve in its 'forward position, with the result that plate valve is moved Vfrom its forward position shown to its rearward position, whereupori iiuid pressure entering the valve through the passage l may then flow across the front face of the valve plate and enter the left-hand end of the cylinder ll via the passage lil. rThis causes the ringer to reverse its direction and return to its initial position shown, during which it the port 'Iii and thereby causes pressure to build up the right-hand end of the cylinder and the rear faceof the plate valve via the port '13 and passage fil. The plate valve ref rais in its rearward position until the continued forward ioveerit of the plunger reopens the port 'I5 to vent the left-hand end of the cylinder, whereupon the plate valve 'then shifts again to its 'fojard position shownfor the beginning of the next operating cycle. Each time the plunger 68 returns to its forward position shown in `Figure 2 it delivers an impact blow to the shank l! oi' the clip pusher member 2. Thisactien continues during and after completion of the forward advancement of the piston in the iorward direction; and it will thus be seen that both an intermittent anda progressive movement of the pusher meinber- 62 are therebyeiected The -clip 'pusher member 62 also constitutes the striker portion orf the percussive hammer. Its ein is formed 'site the "usual tapered shank ell which e xtends into the bore of the hammer C yiiirdf "trough s correspondingly tapered thrust supporting l'iher '8 I. longitudinally split collar 82 held together by an encircling snap ring isprOvided for loosely s ec`1 ri'ng the plunger ndfwissi'rl the hammer cylinder ti. inturned 'sense-s :it and at at opposite ends ci this 'collar engage peripheral grooves 86 and '(87 on the cylinder El and forwardly of the tapered shank d0 the pusher inenber d62. `|`The grooves 86 and er are slightly wider 'than the thick-ness of the @Jhd EE IVIVide the pusher member witl`i 'su iiio`ien't longitudinal freedom of movement relative to the hammer pistn e1 'for maximurntransmission of the plu-nger impacts to the clip 211 heilig clinched.

j As stated earlier, the plates 8 and 9 of the lhead 4 serve toguide the pusher member 62 during its sliding movements toward and away from the anvil.l Adjacent their juncture with the base 5 of 4the head the opposing inner faces`90 and 9| of these plates are counterbored, as shown at 92 and 93in` Figures 4 and 5,` to provide clearance for the collar 82 and the forward end'of the hammer 'cylinder 61 during their movements with the pusher member 62. At the forward end of this counterbore are semi-circular abutments 94 and 95 on the plates 8 and 9 (formed as by drilling aligned holes 96 and91 throughthe plates at that point). In the event the tool is operated without being loaded with a clip to be clinched, pins 98 and 99 which are carried by the` pusher member 62 engage these abutments, thereby limiting the forward travel of the pusher member and preventing its nose portion? 63 from striking the `anvil forming faces 22 and 230i the rockers.

The rear end 3 of the cylinder 2 is provided with inlet and exhaust passageways I I2 and I3 respectively which are in alternate communication "with the interior of the bore 1 of cylinder 2 through a conventional slide valve I I4 and a common inlet and exhaust passage I I 5. Fluid, for example, air supplied under pressure through a hose I I8 connected to the inlet passage I I2, urges the valve I I4 upwardly from its position as shown in Figure 2 to a position `blocking communication between the inlet passage I I2 and passage I I5 and opening communication between exhaust passage I |3 and passage I I5, all in a manner which will be readily understood.

The valve I I4 bears at its upper end against the rear arm |21 of a bell crank |28. This bell crank is journaled'in a cored passage extending longitudinally through the wall of cylinder 2 and is provided atk its forward end with the finger operated control lever |29, by depressing which the operator may force the valve ||4 downwardly to operate the tool. A dog |30 is secured to the bell crank |28 in proper angular relation with the arm |21 so as to strike the outer surface of the cylinder 2 when the valve ||4 is in its uppermost or exhaust position.

Secured to the plate 8 of the yoke-shaped head 4, as by the bolts I6 and I1 about which the rockers I8 and I9 are pivoted, is a feed magazine I4I. This magazine comprises a flexible monorail or band |42 made of spring steel or equivalent material. Adjacent one edge |43 of the band are secured a succession of L-section brackets |44, interspaced from each other as indicated at |45. One leg I 46 of each bracket |44 is spaced from one side |41 of the band, and the adjoining other leg |48 extends transversely thereto in spaced relation from the edge |49 of the band. A similarly shaped but heavier constructed bracket |56 connects one end of the band to the plate 8 by the bolts I6 and |1 as aforesaid. U-shaped clips 24 straddle the edge |49 of the band with one of their legs, either 25 or 26, disposed between the band and the bracket leg I 46, as indicated in dotted lines in Figure 6. During operation of the tool, clips are stacked in this manner in end-toend relation along the band and feed by gravity through the opening 39 to the loading ystation defined by the wall members 31' and 38 between the plates 8 and 9 of the tool head 4. The upperend (not shown) of the band |42 may be suspended from a fixed support and the magazine I4 I be used tosupport the weight of the tool during operation. Further, the upper end of the band may be continuously fed with clips from a hopper. The

interspacing `of the brackets |44 preserves vthe flexibility of the band I 42, vthereby allowing the tool to be maneuvered as necessary relative to the work during operation.

The operation of the tool to clinch a clip 24 about wires I4 and|5 or other work will now be described. With finger pressure released from the lever I 29 the valve I I 4 automatically rises due to air pressure in the line |I6 to open the rear end of the cylinder 2 to atmosphere through the exhaust passage I I3, and the retracting spring 12 thereupon withdraws the percussive hammer piston 66 and its attached pusher member 62 toward the rear end 3 of the cylinder 2 until the clip engaging nose portion 63 is disposed just rearwardly of the wall members 31 and 38. The withdrawal of the cam surfaces 64 and'65 carried by the clip pusher member 62 allows the springs 29 and 39 to draw the rollers 21 and 28 toward each other and separate the anvil-forming hook-shaped ends 28 and 2| of the rockers I8 and I9. The wires I4 and I5 may then be engaged in the notches I2 and `|3 of the plates'8 and 9 ready for a clinching operation.

A clip 24 will then drop by gravity from the feed magazine |4I into the space between the wall members 31 and 38 Aand be retained fully seated therein by the magnet 49. The doors 40 and 4|, being urged by their springs 44 and 45, will be in their normally closed positions (as shown in Figure 3) and retain the clip 24 upright in loosely abutting relation with pusher member nose portion 63.

The operator then by depressing the finger lever |29 moves the valve I|4 downwardly to close off the exhaust passage I3 and open the cylinder to air under pressure from the rline II6 through the inlet passage ||2 and the common passage I|5. As pressure builds up in the cylinder'bore 1 behind the percussive hammer piston 66, the latter is driven forward against its retracting spring 12, moving the clip pusher member 62 forwardly to force the clip 24 legs foremost through the doors 48 and 4| and toward the hook shaped rocker ends 20 and 2|. With continued travel of the clip pusher member 62 in this direction, its cam surfaces 64 and 65 engage the rollers 21 and 28, spreading them apart and swinging the hook-shaped ends 28 and`2| of the rockers I8 and I9 into anvil forming relation about the wires I4 and I5.

In addition to the progressive forward movement of the piston 66, the pressurizing of the rear end of the cylinder 2 causes the plunger 68 to reciprocate in the percussive hammer cylinder y61 and deliver striking blows to the pusher mem- `clip 24, The pressure within the rear end of the cylinder 2 is relatively low at the beginning of the operation and increases gradually as the retracting spring 12 is compressed during the forward movement of the piston 66 and `clip pusher member 62, hence the intensity of the blows delivered to the clip 24 increases to its maximum when the clip reaches the solid backing afforded by the anvil. A thorough set of the clip legs25 and 26 around the wires I4 and I5 is thereby nallyobtained with the employment of the full powerl capacity of the tool. Such a permanent set is desired to prevent any tendency of the legs ofthe clip tounwind due to natural resilience when the clip pusher member is withdrawn.

-A ltool constructed as above `described .has

WILLIAM D. CHILTON. i

References Cited in the 111e of this patent UNITED STATES PATENTS Number Name Date Peterson June 16, 1931-- Maynard sept. 22, 1936 1 Rosenberg Nov. 16, 1937 Harrison x f Feb. 21, 1939 Number Number Name Date Curtiss Oct. 31, 1939 Sorensen Dec. 19, 1939 Green June 25, 1940 Smith July 23, 1940 Bangs May 20, 1941 Williams Dec. 23, 1941 Forss Mar. 12, 1946 FOREIGN PATENTS Country Date Germany Mar. 2, 1932l 

